Alkaline battery



IN1/ENT BY M meA/EH W. W. GARY, JR

ALKALINE BATTERY Flled Oct 30, 1950 June 16, 1953 Patented June 1 6, 1953 UNITED STATES PAT ALKALINE BATTERY" I( Wright W. Gary, Jr., Pasadena, Calif.Vw M l Application October 30, 19501,'Stv21ia1N0r192,8i3Y

9 claims. (c1. vnie- 28T This invention relates to storage batteries, `and particularly to storage batteries of thealkaline type.

known. This type of battery has many advan- Nickel cadmium-alkaline storage batteries arev tages over the lead-acid type of battery, such as s for use in starting motors and the like. To obtain batteries suitable for starting purposes withv this required output, thin plates of the order of one to twomillimeters thick, spaced less than one millimeter apart are necessary. To build such batteries, construction costs are excessive, because of the low conductivity of the electrolyte and the active chemicals. Another of its disadvantages is in the sloughing of the active chemicals. Also, many alkaline type batteries failed because of the bursting of the positive plate due to the expansion of the nickel vhydroxide, which may expand as much as thirtyve percent over its original volume.

The battery of my construction overcomes these disadvantages and provides an economical, rugged, and high ampere voltage alkaline battery. For instance, the porosity of the external membrane preserves all chemicals within the plate, while the chemical is applied in a thin sheet in contact with a continuous conductor. The maximum relation of chemical volume and weight to cell electrolyte is obtained, while the plates are nested without spacers to eliminate individual platemovement causing erosion in use and preventing splashing of free electrolyte. The plates are so nested that each cell has a maximum rigidity, pressure being exerted on the complete plate surfaces. By a large number of plates, eiiervescing of the cell is reduced to a minimum along with current loss due to the internal resistance.

The principal object of the invention, therefore, is to provide an improved alkaline type of storage battery.

Another object of the invention is to provide an alkaline type battery capable of having a higher discharge rate with a minimum of weight and cost relative to available ampere hours.

A further object of the invention is to produce an alkaline type storage battery having a high 'of Fig. 2. Y

ratio between active chemical and structuralrequirements. i' f Although the novel features which are believed to` be characteristic -of this invention will be pointed out with particularity in the appended n claims, the manner of its organization and the mode of its operation `will be better understood by referring to the following description, read in conjunction with the accompanying drawings, forming 1a 4part thereof, in which:

Fig. 1 is a perspective view of a battery conl structed in accordance with my invention.

Fig. 2 is a cross-sectionalview taken along the yline 2--2 of Fig. 1.

Fig. 3 is a detailed view of the plate construction, and f Y y Fig., 4 is an end view taken along thel line 4--4 Referring Anow to the drawings, in which the same numerals identify like elements, the battery shownv has an outer, rectangular` case 5 having extended'bosses B, 1, and 8 in the top 9 thereof. The battery shown in the ilgures isl onehaving only three'cells, but it is to be understood that any number ofrcells may be added utilizing the same construction to loe-described hereinafter. Sinceeach cell provides approximately 1.2 volts,

a three-cell battery would provide 3.6 voltswhile n a five-cellbattery would provide six volts.

Referring now to Figs. 2, 3, and v4, each negative and positive plate is constructed of porous backing membranes il, these membranes being made of such-material asl filter paper, parchment, or suitable woven .cotton or plastic; fabric, or other such materialwhich is non-reactive with the electrolyte. The .thickness may be that of usual bondpaper. In Fig.'3, one negative plate 2 has on each side thereof a positive plate, as shown `at,.3and 4.A Sprayed or painted on one surface of each yof the membranes Il of positive plates 3 and 4,`is acoating of nickel-hydroxide hydrogel` AI2, between which is a nickel foil conductor gridv I3, which may be etched, grilled, and/or corrugated to provide a greater initial bond between the foil and hydrogel and to increase the surface area therebetween. Thus, two backing membranes Il., each with a layer `of nickel hydroxide hydrogel I`2and the foil I3 between the layers oflhydrogehprovide one posi- `tive plate. The hydrogel doesvnot extend to the the.membTanesbeingseaIed around a lead as sho.wn at L5 extendingzfromthemembranes. By

therefore, are `mot cimmerse'dii sealing the edges of the membranes. a, porous envelope is provided so that the active chemical will be retained within the envelope without spalling or sloughing. y

To form the negative plate, two similar porous membrane backings II are used, on which is sprayed or painted finely divided electrolytically active cadmium, such as cadmium oxide I8. This cadmium oxide ,has mixed with it .finely divided iron oxide toiiprevent-:caking ofithe-fcadmiumioxide to increase its chemical activity. Between the cadmium oxide-iron oxide layers I8, is another nickel foil conductor vgrid '20, this unit forming the negative plate 2. membranes are .sealed at I6 and I1 to contain the chemicals Within the porous membrane envelope so formed, a lead lfexindiigifzmm the grid 2D around which the membranes are sealed.

Again, the edges auf nickel hydroxide, graphite, nickel flakes, or other non-reactive conductors may be mixed with the nickelsalt solution. Tileseconductors provide a :nucleus around'which `the freshly precipitated hydrogel'is formed, To prevent possible cracking ofthe hydrogel and to increase its strength Viivhen in very thin layers, an inert iiller material @may also be added, such materials being paper pulp fibre, cotton, asbestos, or the like. lflhehydroge'l is then filtered to remove any exicessfsolutionand,Washed to remove Sonates, car- The outer surfaces of the membranesrol each plate have their backs in contact.

r.After the zneces'saryinumber :of itheseiplates faire arranged side by side, as shown in Figzftdprovide La cell of the :desired :rampere ihour output,

"the plates vare enclosed :Within man selectrolyte leak-'proof sack or 'bag 2.5otherf.cells1being yfenclosed :in similar '.fsacks, vsuchfas wat 22B' and :a2-11, These .sacks may i bec-'of material-.sachets neoprene rubber, yor suitable plasticsthe `open-.ends :of: the bags being .attached :to th'e'irmer edgesro'f @the bosses 5, 1, andfcdfithe ,coveriarespectivlygin Yany suitable imanner, as by bin-dings 2|.. 1"The plates are :.immersedin "an :electrolytei dfnpotas.-

Lsi'um hydroxide, :and coneeway lnent Soaps linver holes-through bosses B, 1, and Bnsuch as shown .at mi ,1 :land ei, 'are sprovilded, :thus allowing i ready escape of liberated gases, but

ingressFotfatmoslzherebearing .carbon dioxide.

All negative foils in one cell are connected eachzplate in one cellzare connected together b 'y rzconnectingizheir: respec- -tive Vleads ii 5" tofa'husabarnsuchaas shown; atp-1213 :in cell lQ25. 1 "Ehe :busrbar :Jiisconnecteditozter minal i'i5','.and abusi bar :2273s ccennectedito .'terminal fil. :Siinilaribars iin .thefeotl'ier'fcellsnare connected tito 1. respect-ire terminals 2.41 ato i511, in-

clusive 4fLhef-ne'g'ative andizpositiizezaerminalsifare then connected -ito .feachiother Aicy-s straps Stand 29, as showninfigslllandrZ. .l i

`After f each 1 cell sisi completed, `it :ibe aar- :rangedfas: shown insFigB, aiterawhich pressure plates 3era/nd elfzmaypbenapplied andaasplurality hold the plates 1in. position'. AAThere flaresspri-ngs on each-.boltfto appl-"y:axpre'determinedipressure `on the :battery-:pila Landfwhichipermitnexpansion 'be' notedf that eachgplatefisanind-ividual unitifin which 'theI` cleeniicaliscontainedwlrileleaclrfcll is a separate 'unit `in@xiliiclrthe@electrolytis contained. ''Iheplinfaflityiiiboltsr 32? M9135; inclusive,

he electrolyte, nor i are they finvooniiact viitlrainyrchemicals.

"- Oney .of-s the;feaimrnstofethehatteryfisiithemiclrel bonates, and other soluble salts, and pressed at from the hydrogel sufient to promote a plastic .finassroi ithenonsistency of molding clay.V Drying as `carefully, avoided/so ...as ,not .-to destroy :the :hy-

drogel structure. This active chemical is lthen applied-to the backing vi'neinbranes I i, as shown .at fI-2,.-a-ndfin .the manner described above.

By:having;the unimpregnatedrsides ofzthe membranes Il facing outwardly, fthey are f'ree f rom .the ichernicals and are -noneconductive, ,which .permits their being nested with vother :platesiof foppnsite :polarity The membranes ,also -allowfthe escape ,of any gasses vv-hichv might foe liberated, which prevents gasp-1 Vaporfbindingfthat .might otherwise exist inthe nell,y The hydrogelxlias. adhesive characteristics, :which .causait to, adhereato fthe fmembraneibackine LI andasoft thefconductive foil grids t3,:.thepressurezannlied#byhome2 :to 35, inclusive, insuring maximum ,conductor-- Ichemical `Contact .and .nii imurn plate volume. :By =Sea1ine vthe hydroeel :v flain-tnemembranes Greepaeethereof,-overqextendcd-luse,#through `expansion-I and contraction, is prevented.

After the battery is assembled, as described above, it should loe'gchareed 'first at .a high rate ,ofachareeffora shortneliodiof time, andethcnfat a :low rate. During-the `high ratefof charge the concentration Aof the potassium hydroxide electrolyte should .beunder one percent pr less-,than 1.008 speciiicgravity. Byfthis highrategof charge, fa, highermolecular bend between thegactive chemical and, the foil conductor ,grid-is achieved, :as Well as producing :a very dense,- active f, chemical andfetching of the-ion. in thezseeond'richarging step, 1 the ,electrolyte concentration is 'increased to; 251-27 percentpr 13239-11270 speeicgraV-ity.

; Iclaim:

fl. .1A batte-ry cell construction YOfthe alkaline ltype icomprising a plurality soi" interposed :posi- .tive andf negative plates, saidv positive plates including an individually sealed v.envelope ofporous .membrana V,tliinlayers offnickel hydroxide hydrogel jin` a soft plastic. mass covering substantiallyzthe Ventireinternal Asurfacefof said membra-nasa 'foil conductor :between -fsai'd :hydrogel l layers; andi extending externallyfof'fzsaid; envelope,

. said; negativeplates beinginterposedbetweenrsaid hydroxidewhydogelusedinrdormngthespositive '15 V12.1. A- battery u celi.iconstructiong-in :accordance with claim 1, in which said cadmium oxide layers have mixed therein finely divided iron oxide, and said plates are enclosed in a non-porous flexible sack filled with potassium hydroxide.

3. A battery cell construction in accordance with claim 1, in which is provided a non-porous flexible sack for said plates, backing members at the end surfaces of the end sacks, and tensioning bolts between said members at the edges of said sacks and external thereto.

4. An alkaline battery comprising a casing, a plurality of cells in said casing, each of said cells comprising a plurality of interposed positive plates and negative plates, each of said positive plates including an individual envelope of parallel membranes, thin layers of nickel hydroxide hydrogel coating substantially the entire interior surfaces of said membranes, a conductor foil between said hydrogen layers, said membranes being sealed at the edges thereof to form said envelope, and each of said negative plates including an individual envelope of a pair of parallel membranes, thin layers of a combination of cadmium and iron oxides coating substantially the entire interior surfaces of said second pair of membranes, a conductor foil between said cadmium layers, said membranes being sealed at the edges thereof to form said envelope, the outer surfaces of the membranes of said negative plates physically contacting the outer surfaces of the membranes of said positive plates, a non-porous ilexible sack enclosing all the plates of each cell, an electrolyte of potassium hydroxide in each sack and immersing said plates, pressure members along the outer surfaces of the end cells, a plurality of bolts joining said members at the edges of said cells and externally thereof, and tensioning means on said bolts for permitting said end members to move toward and away from one another. during expansion and contraction of said cells.

5. An alkaline battery cell construction, comprising two spaced porous membranes in parallel planes, thin coatings of nickel hydroxide hydrogel in a soft plastic mass on the opposing surfaces of said membranes, said coatings extending over substantially the entire opposing surfaces of said membranes, a thin conducting grid foil between and in contact with said coatings, said membranes being sealed around the peripheral edges thereof and said foil extending beyond the edges of said membranes at one point, said above mentioned construction forming a positive plate of said cell, two additional, spaced porous membranes in planes parallel to said rst mentioned membranes, thin coatings of a combination of cadmium and iron oxides on the opposing surfaces of said last mentioned membranes, said coatings extending over substantially the entire opposing surfaces of said last mentioned membranes, and a thin conductor grid foil between and in contact with said last mentioned coatings, said last mentioned membranes being sealed around the peripheral edges thereof, and said foil extending beyond the edges of said membranes at one point, said last mentioned construction forming a negative plate of said cell, the opposing external surfaces of said membranes of said respective plates being in contact with one another.

6. The method of preparing a nickel hydroxide hydrogel for an alkaline battery, comprising rst mixing graphite flakes with a dilute, aqueus, boiling solution of a nickel salt, secondly, slowly mixing an aqueous solution of sodium hydroxide to said dilute, aqueous solution of the nickel salt, agitating said solution during mixing, thirdly, ltering the resulting vprecipitate of nickel hydroxide hydrogel to remove excess solution, fourthly, washing the precipitate to remove soluble salts therefrom, and then applying pressure to said precipitate to form a plastic mass of hydrogel of the consist cncy of molding clay.

7. The method of claim 6, in which an inert filler is mixed with said solution of nickel salt before the adding of said sodium hydroxide.

8. A homogeneous active material for an alkaline storage battery electrode having a plastic mass of the consistency of molding clay formed by slowly adding a concentrated solution of sodium hydroxide to a dilute aqueous boiling solution of a nickel salt in which a conductive material has been previously mixed, said solution being agitated during mixing and precipitation, said precipitate being washed to remove soluble salts therefrom.

9. A homogeneous active material in accordance with claim 8, in which an inert fibrous filler is mixed with said nickel salt before the addition of kSaid sodium hydroxide.

WRIGHT W, GARY, JR.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 309,939 Faure Dec, 30, 1884 914,372 Edison Mar. 2, 1909 1,083,356 Edison Jan. 6, 1914 1,104,898 Hubble July 28, 1914 1,167,484 Edison Jan. 11, 1916 1,366,223 Wales Jan. 18, 1921 1,377,194 Edison May 10, 1921 1,379,088 Edisonv May 24, 1921 1,649,579 Edison Nov. 15, 1927 1,740,518 Miller Dec. 24, 1929` 1,884,166 Otsuka et al Oct. 25, 1932 1,879,904 Kranzlein et al. Sept. 27, 1932 2,157,629 Rolph May 9, 1939 2,184,373 Adams Dec. 26, 1939 2,213,128 Langguth Aug, 27, 1940 FOREIGN PATENTS Number Country Date 390,122 Great Britain 1933 

1. A BATTERY CELL CONSTRUCTION OF THE ALKALINE TYPE COMPRISING A PLURALITY OF INTERPOSED POSITIVE AND NEGATIVE PLATES, AND POSITIVE PLATES INCLUDING AN INDIVIDUALLY SEALED ENVELOPE OF POROUS MEMBRANE, THIN LAYERS OF NICKEL HYDROXIDE HYDROGEL IN A SOFT PLASTIC MASS COVERING SUBSTANTIALLY THE ENTIRE INTERNAL SURFACE OF SAID MEMBRANE, A FOIL CONDUCTOR BETWEEN SAID HYDROGEL LAYERS AND EXTENDING EXTERNALLY OF SAID ENVELOPE, SAID NEGATIVE PLATES BEING INTERPOSED BETWEEN SAID POSITIVE PLATES AND INCLUDING AN INDIVIDUALLY SEALED ENVELOE OF POROUS MEMBRANE, THIN LAYERS OF CADMIUM OXIDE COVERING SUBSTANTIALLY THE EN- 